Several security issues were fixed in the kernel.
A flaw was found in how the Linux kernel passed the replacement session keyring to a child process. An unprivileged local user could exploit this flaw to cause a denial of service (panic). (CVE-2012-2745)
19 September 2012
A security issue affects these releases of Ubuntu and its derivatives:
Several security issues were fixed in the kernel.
A flaw was found in how the Linux kernel passed the replacement session keyring to a child process. An unprivileged local user could exploit this flaw to cause a denial of service (panic). (CVE-2012-2745)
Ben Hutchings reported a flaw in the Linux kernel with some network drivers that support TSO (TCP segment offload). A local or peer user could exploit this flaw to to cause a denial of service. (CVE-2012-3412)
Jay Fenlason and Doug Ledford discovered a bug in the Linux kernel implementation of RDS sockets. A local unprivileged user could potentially use this flaw to read privileged information from the kernel. (CVE-2012-3430)
A flaw was discovered in the madvise feature of the Linux kernel’s memory subsystem. An unprivileged local use could exploit the flaw to cause a denial of service (crash the system). (CVE-2012-3511)
The problem can be corrected by updating your system to the following package versions:
To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.
After a standard system update you need to reboot your computer to make all the necessary changes.
ATTENTION: Due to an unavoidable ABI change the kernel updates have been given a new version number, which requires you to recompile and reinstall all third party kernel modules you might have installed. If you use linux-restricted-modules, you have to update that package as well to get modules which work with the new kernel version. Unless you manually uninstalled the standard kernel metapackages (e.g. linux-generic, linux-server, linux-powerpc), a standard system upgrade will automatically perform this as well.